Which imaging finding confirms lung re-expansion after chest-tube placement?

• A. Thoracic CT showing persistent pneumothorax.
• B. Ultrasound showing pleural effusion.
• C. Chest radiograph showing expanded lung and decreased pleural effusion/air; absence of significant pneumothorax.
• D. MRI of chest showing no fluid.

Answer: (C)

After chest-tube placement, confirming lung re-expansion relies on imaging that shows the lung has filled the space and the pleural cavity is clear of air and fluid. The most reliable sign is a chest radiograph demonstrating an expanded lung with decreased pleural air and/or effusion, and no significant pneumothorax remaining. This demonstrates that evacuation of air and fluid has allowed the lung to reopen and stabilize.

CT showing a persistent pneumothorax would indicate incomplete re-expansion, not confirmation of it. Ultrasound identifying pleural effusion alone doesn’t confirm that the lung has re-expanded or that the pneumothorax has resolved. MRI isn’t the standard modality for acute post-procedure assessment of the chest and wouldn’t specifically indicate re-expansion in the way a chest radiograph does.